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Unread 01-23-2017, 02:55 PM   #1
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Thanks again Drew, I agree that the more we study this topic, the better.

Your other assumption is, there was a standard "agreement" between the US makers and their British counterparts to use the same protocols for testing, to include a standard location for the crusher on the pressure gun, the same crusher diameter/length, and the same chemically pure lead or lead alloy whichever it was. Do we know if there was any such agreement? I've never read of anything like that in period literature and frankly I don't believe the Brits tried to coordinate their pressure testing apparatus and protocols with what the US makers were doing.

All told and thanks to your work, it seems that Burrard had a good handle on a conversion formula for pressures as measured by the British. Does Burrard specifically mention in his book that his formula applies to the US makers and their protocols when they measured tons or tons/sq inch with the old lead crusher technology?

Also who has any references to "Burrard's Conversion" in recognized US shotgun ballistic literature? I've seen many references where American makers reported pressure in "tons" and generally that's been accepted as: tons X 2200 (as I learned in grade school) or as tons X 2240 (as the accepted value is today). The difference between using the factors 2200 or 2240 is somewhat insignificant relative to this discussion.

I agree of course that old US lead crusher numbers should be multiplied by 1.10 to 1.15 to convert to transducer psi. Nowhere have I read or seen anything other than: tons X factor X 1.10 to 1.15 to convert to approximate psi.

I thank you again Drew for this effort and all the other study work you do. I hope to meet you some day.
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